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Related papers: Dynamical twisted mass fermions

200 papers

We estimate the effects of dynamical fermions by extrapolating to positive flavour numbers the results from negative values obtained by adding to the pure gauge sector a fermion action where the fields obey a Bose statistics: the bermions.

High Energy Physics - Lattice · Physics 2015-06-25 G. M. de Divitiis , R. Frezzotti , M. Guagnelli , M. Masetti , R. Petronzio

We describe a new set of gauge configurations generated within the CLS effort. These ensembles have N_f=2+1 flavors of non-perturbatively improved Wilson fermions in the sea with the Luescher-Weisz action used for the gluons. Open boundary…

We present a 1-loop perturbative calculation of the fermion propagator, up to O(a^2) (a: lattice spacing). The fermions are described by Wilson, clover and twisted-mass actions; for gluons we use Symanzik improved actions (Plaquette,…

High Energy Physics - Lattice · Physics 2010-11-05 Martha Constantinou , Haralambos Panagopoulos , Fotos Stylianou

We present the results of the recent high precision lattice calculation of the average up/down, strange and charm quark masses performed by ETMC with Nf=2 twisted mass Wilson fermions. The analysis includes data at four values of the…

High Energy Physics - Lattice · Physics 2011-04-22 B. Blossier , P. Dimopoulos , R. Frezzotti , V. Lubicz , M. Petschlies , G. C. Rossi , F. Sanfilippo , S. Simula , C. Tarantino

We explore aspects of the phase structure of SU(2) and SU(3) lattice gauge theories at strong coupling with many flavours $N_f$ of Wilson fermions in the fundamental representation. The pseudoscalar meson mass as a function of hopping…

High Energy Physics - Lattice · Physics 2010-04-30 Kei-ichi Nagai , Georgina Carrillo-Ruiz , Gergana Koleva , Randy Lewis

We present results on the nucleon tensor form factors and first moment of the transversity distribution using maximally twisted mass fermions. We analyze two Nf=2+1+1 ensembles having pion masses of 213 MeV and 373 MeV with lattice spacing…

High Energy Physics - Lattice · Physics 2013-11-20 Constantia Alexandrou , Martha Constantinou , Karl Jansen , Giannis Koutsou , Haralambos Panagopoulos

We apply the relative weights method to extract an effective Polyakov line action, at finite chemical potential, from an underlying $SU(3)$ lattice gauge theory with dynamical fermions. The center-symmetry breaking terms in the effective…

High Energy Physics - Lattice · Physics 2015-10-14 Roman Höllwieser , Jeff Greensite

We discuss the behavior of free perfect staggered fermions and truncated versions thereof. The study includes flavor non-degenerate masses. We suggest a new blocking scheme, which provides excellent locality of the perfect lattice action. A…

High Energy Physics - Lattice · Physics 2007-05-23 W. Bietenholz , H. Dilger

We present results for the eta prime meson and the topological susceptibility in two flavour lattice QCD. The results are obtained using Wilson twisted mass fermions at maximal twist with pion masses ranging from 340 MeV down to the…

We have investigated QCD with two flavors of degenerate fermions using a Symanzik-improved lattice action for both the gauge and fermion actions. Our study focuses on the deconfinement transition on an $N_t=4$ lattice. Having located the…

We present results for the light, strange and charm quark masses using $N_f=2+1+1$ twisted mass fermion ensembles at three values of the lattice spacing, including two ensembles simulated with the physical value of the pion mass. The…

We report on our first set of results for charm physics, using a mixed-action setup with maximally twisted valence fermions on CLS $N_f=2+1$ ensembles. This setup avoids the need of improvement coefficients to subtract $O(am_c)$ effects.…

High Energy Physics - Lattice · Physics 2022-12-22 Alessandro Conigli , Julien Frison , Gregorio Herdoíza , Carlos Pena , Alejandro Sáez , Javier Ugarrio

We present scaling studies for heavy-quark observables calculated with an $O(a^2)$-improved fermion action on tree-level Symanzik improved gauge configurations. Lattices of $1/a = $ 2.0-3.8 GeV with an equal physical volume 1.6 fm are used.…

High Energy Physics - Lattice · Physics 2014-12-22 Yong-Gwi Cho , Shoji Hashimoto , Jun-Ichi Noaki , Takashi Kaneko , Andreas Jüttner , Justus Tsang , Marina Marinkovic

The effective potential for the Wilson loop in the SU(2) gauge theory with N_f massive fundamental and N_a massive adjoint fermions on S^1 x M^4 is computed at the one-loop level, assuming periodic boundary conditions for the gauge field…

High Energy Physics - Phenomenology · Physics 2009-11-10 Muge Boz , Namik K. Pak

We discuss the computation of the topological susceptibility using the method of spectral projectors and dynamical twisted mass fermions. We present our analysis concerning the O(a)-improvement of the topological susceptibility and we show…

High Energy Physics - Lattice · Physics 2013-12-13 Krzysztof Cichy , Elena Garcia-Ramos , Karl Jansen , Andrea Shindler

We perform the scale setting procedure of a mixed action setup consisting of valence Wilson twisted mass fermions at maximal twist on CLS ensembles with $N_f=2+1$ flavours of $O(a)$-improved Wilson sea quarks. We determine the gradient flow…

High Energy Physics - Lattice · Physics 2024-01-25 Alejandro Saez , Alessandro Conigli , Julien Frison , Gregorio Herdoíza , Carlos Pena

We present results on the isovector and isoscalar nucleon axial form factors including disconnected contributions,using an ensemble of $N_f =2$ twisted mass clover- improved Wilson fermions simulated with approximately the physical value of…

We describe and test a nonperturbatively improved single-plaquette lattice action for 4-d SU(2) and SU(3) pure gauge theory, which suppresses large fluctuations of the plaquette, without requiring the naive continuum limit for smooth…

High Energy Physics - Lattice · Physics 2016-04-20 Debasish Banerjee , Michael Bögli , Kieran Holland , Ferenc Niedermayer , Michele Pepe , Urs Wenger , Uwe-Jens Wiese

We investigate the continuum limit scaling of the scalar condensate in the $N_f=2$ Schwinger model on the lattice. We employ maximally twisted mass Wilson fermions and overlap fermions. We compute the scalar condensate by taking the trace…

High Energy Physics - Lattice · Physics 2009-07-30 Kei-ichi Nagai , Nils Christian , Karl Jansen , Beatrix Pollakowski

We present the current status of lattice simulations with N_f=2 maximally twisted mass Wilson fermions at finite temperature. In particular, the determination of the thermal transition temperature is discussed.